Always ask the actor to read the scene twice! See whether they can take direction and how big their range is. As an actor it feels better if I can do something twice, and change it up.
Even if I’m not good for this role I may suddenly be good for another role that they haven’t cast, (re: Episodic TV) or are going to cast in the future. I got called for a role once because of an audition a year before. They remembered me!